''Argosarchus'' is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Phasmatidae The Phasmatidae are a family (biology), family of the stick insects (order (biology), order Phasmatodea). They belong to the Superfamily (zoology), superfamily Anareolatae of suborder Verophasmatodea. Like many of their relatives, the Phasmatida ...

containing the single

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

''Argosarchus horridus'', or the New Zealand bristly stick insect, a

stick insect The Phasmatodea (also known as Phasmida or Phasmatoptera) are an order of insects whose members are variously known as stick insects, stick bugs, walkingsticks, stick animals, or bug sticks. They are also occasionally referred to as Devil's da ...

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to New Zealand (''Argosarchus spiniger'' is now considered a junior synonym of ''A. horridus'').http://phasmida.archive.speciesfile.org/Common/basic/Taxa.aspx?TaxonNameID=1201278 The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

''horridus'' means 'bristly' in Latin, likely referring to its spiny thorax.

Description

Females can reach up to (but are usually 12–15 cm), making this endemic species the longest New Zealand insect. A distinguishing feature is the coxa of the two forelegs is purple or pink. Females are much larger than males and have a visibly spiny

thorax The thorax (: thoraces or thoraxes) or chest is a part of the anatomy of mammals and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main di ...

. Males are much skinnier and shorter, usually up to . The colour of ''A. horridus'' ranges from pale white to dark brown, with females usually being grey and males being a dark greenish-brown or dark brown. Males have longer spines but less of them.

Life cycle and mating behaviour

Argosarchus horridus by George Vernon Hudson

Like many other New Zealand stick insects, ''A. horridus'' is facultatively

parthenogenetic Parthenogenesis (; from the Greek + ) is a natural form of asexual reproduction in which the embryo develops directly from an egg without need for fertilization. In animals, parthenogenesis means the development of an embryo from an unfertiliz ...

. Because of that, some populations consist of only females who reproduce asexually, while other populations have both males and females and can reproduce by either

asexual Asexual or Asexuals may refer to: *Asexual reproduction **Asexual reproduction in starfish *Asexuality, the lack of sexual attraction to anyone or lack of interest in or desire for sexual activity. **Gray asexuality, the spectrum between asexualit ...

sexual reproduction Sexual reproduction is a type of reproduction that involves a complex life cycle in which a gamete ( haploid reproductive cells, such as a sperm or egg cell) with a single set of chromosomes combines with another gamete to produce a zygote tha ...

. Adults hatch in early summer and can be seen hanging off their host plant, feeding on it. They are mostly active at night, with males actively searching for females. Males will mate with females by climbing on to their back, and using the toothed claspers near their genitalia to attach and begin copulation. Males may remain clasped onto a female, even if not mating, in order to mate-guard. Mature females lay eggs continuously throughout their adult life, indiscriminately dropping them to the ground. The large eggs resemble plant seeds, and are well-camouflaged on the forest floor. Eggs hatch in early spring, and

nymph A nymph (; ; sometimes spelled nymphe) is a minor female nature deity in ancient Greek folklore. Distinct from other Greek goddesses, nymphs are generally regarded as personifications of nature; they are typically tied to a specific place, land ...

s resemble miniature adults. Like other stick insects, ''A. horridus'' is

hemimetabolous Hemimetabolism or hemimetaboly, also called partial metamorphosis and paurometabolism,McGavin, George C. ''Essential Entomology: An Order-by-Order Introduction''. Oxford: Oxford University Press, 2001. pp. 20. is the mode of development of certain ...

, and nymphs grow by moulting, going through six instars until final adulthood. Des Helmore Desmond W. Helmore (born 1940) is a New Zealand artist and illustrator, known both for his fine art and for his scientific work depicting insects, not least illustrating the New Zealand Arthropod Collection. One of the country's most noted and ...

Description

Life cycle and mating behaviour

Habitat and distribution

See also

References

External links